Stated Ibn Masʿūd (raḍī Allāhu ʿʿʿanhu), “If a Believer were to enter a mosque containing one thousand people, there being in it only one Believer, he would come until he sat with him. And if a hypocrite entered a mosque containing one thousand people, there being in it only one hypocrite, he would come until he sat with him.”

Weighing the affairs and acting in accordance to the relative benefit and harm is probably the principle whose neglect is responsible for every fitnah that has befallen the Ummah of Islām. So know it well, and do not fall into the traps that come along with ignorance of it!